Kajal Aggarwal has apparently never done an on screen kiss, whether it is South films, or Bollywood. Since Deepak Tijori's Do Lafzon Ki Kahani is anyways a love story, Kajal was neither prepared, nor aware of a kissing scene whilst they were filming in Malaysia, and it was a shock to her when Randeep Hooda grabbed her and kissed her, while enacting the scene.
It seems Randeep Hooda caught Kajal Aggarwal completely unaware while doing a scene in Malaysia. Kajal and Randeep were doing a highly emotionally volatile scene between them, and Randeep got carried away in the moment of the character, and just grabbed Kajal's face, and went for the lip lock.
Kajal immediately withdrew herself from the scene, and backed off. Although she did not say anything to her co-actor Randeep, keeping in mind his sensibilities as an actor, she called for a cut and just went aside.
Deepak eventually had to go and pacify Kajal, where she asked him to delete the shot that was canned, and go for a clean take. It was a furious moment between Deepak and Kajal, but as they say "all's well that ends well", and so we finally get the south Indian queen doing her first ever Bollywood lip lock on screen.